Precautions / Word of advice for first time OS installer?

Ok so my new computer is coming soon, and the dude won't do pirated Windows XP for me, I'm alright with that. I proposed that he simply installed a free OS to check that the hardware is all set up properly, but he said he can't guarantee everything will be compatible, so in the end, it'll be coming with Vista and a recovery disk.

I intend to just let him do his thing, to confirm everything is in working order, then I'll format and install pirated XP from my own burned disk. I also intend to partition my hard drive for Ubuntu. I googled a little and I guess there will be options while installing XP for that, right?

Is there anything I should know about this setup that won't be compatible with Ubuntu? This is what I'm getting:

Intel Core 2 Duo 3.0Ghz (1333 12MB L2 Cache)
ASUS (DDR21200/PCI-E2.0/ATI CROSSFIRE)
4GB DDR2 800 Kingston Ram CL6 (NEW NANO DESIGN)
2X ASUS HD4850 GDDR3 512MB/2DIV/PCI-E2.0/HDMI (1GB GFX RAM)
Realtek ALC1200, 8-channel High Definition
320GB SEAGATE SATA2 32MB HDD
Coolermaster 700W REAL Power Supply

Any tips or silly things I should avoid doing?

PS. I'm downloading a certain modified version of Windows XP SP3, with most excess Microsoft shit removed, is it advisable to use it? It's got tons of seeders and leechers, so you know it's good... right? XD

ubuntu cd is free, i suggest you order it :D

tips? game onnn!@!!! if im not wrong, ubuntu is its own os

Yep I know that. Already got my own copy of the disk.

So wait, a mod is openly advocating pirating a program that you must purchase?

Hurr durr.